Its true that no one will use it in Main hand for dps nowadays, everyone wants 55 purple, and then moving on to 60 with ch3.
But, if you're playing on a PvP server, a Moa weapon is someting you SHOULD consider using, because it does not drop in PK. Thus very worth Stat tiering it. IMO, way better than using some CS dagger, and u can free up another slot for an Armor to seal.
I just got a Core - Fortitude today, and was very lucky to get the right conversion with the very 1st try, Core - Stealth for Rogue, so i was happy.
But i guess it only apply to PvP servers. PvE doesnt need to worry about pk dropping and limited 8 Sealed items.